EP4069517A1 - Method and system for priming dry printheads - Google Patents

Method and system for priming dry printheads

Info

Publication number
EP4069517A1
EP4069517A1 EP21701123.8A EP21701123A EP4069517A1 EP 4069517 A1 EP4069517 A1 EP 4069517A1 EP 21701123 A EP21701123 A EP 21701123A EP 4069517 A1 EP4069517 A1 EP 4069517A1
Authority
EP
European Patent Office
Prior art keywords
ink
printhead
pump
priming
nozzles
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP21701123.8A
Other languages
German (de)
French (fr)
Other versions
EP4069517B1 (en
Inventor
Zhenya Yourlo
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Memjet Technology Ltd
Original Assignee
Memjet Technology Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Memjet Technology Ltd filed Critical Memjet Technology Ltd
Publication of EP4069517A1 publication Critical patent/EP4069517A1/en
Application granted granted Critical
Publication of EP4069517B1 publication Critical patent/EP4069517B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/17Ink jet characterised by ink handling
    • B41J2/1707Conditioning of the inside of ink supply circuits, e.g. flushing during start-up or shut-down
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/17Ink jet characterised by ink handling
    • B41J2/1714Conditioning of the outside of ink supply systems, e.g. inkjet collector cleaning, ink mist removal
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/135Nozzles
    • B41J2/165Preventing or detecting of nozzle clogging, e.g. cleaning, capping or moistening for nozzles
    • B41J2/16505Caps, spittoons or covers for cleaning or preventing drying out
    • B41J2/16508Caps, spittoons or covers for cleaning or preventing drying out connected with the printer frame
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/135Nozzles
    • B41J2/165Preventing or detecting of nozzle clogging, e.g. cleaning, capping or moistening for nozzles
    • B41J2/16517Cleaning of print head nozzles
    • B41J2/1652Cleaning of print head nozzles by driving a fluid through the nozzles to the outside thereof, e.g. by applying pressure to the inside or vacuum at the outside of the print head
    • B41J2/16526Cleaning of print head nozzles by driving a fluid through the nozzles to the outside thereof, e.g. by applying pressure to the inside or vacuum at the outside of the print head by applying pressure only
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/135Nozzles
    • B41J2/165Preventing or detecting of nozzle clogging, e.g. cleaning, capping or moistening for nozzles
    • B41J2/16517Cleaning of print head nozzles
    • B41J2/1652Cleaning of print head nozzles by driving a fluid through the nozzles to the outside thereof, e.g. by applying pressure to the inside or vacuum at the outside of the print head
    • B41J2/16532Cleaning of print head nozzles by driving a fluid through the nozzles to the outside thereof, e.g. by applying pressure to the inside or vacuum at the outside of the print head by applying vacuum only
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/17Ink jet characterised by ink handling
    • B41J2/175Ink supply systems ; Circuit parts therefor
    • B41J2/17596Ink pumps, ink valves
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01Ink jet
    • B41J2/17Ink jet characterised by ink handling
    • B41J2/18Ink recirculation systems

Definitions

  • This invention relates to method and system for priming dry printheads. It has been developed primarily for facilitating shipment of dry or unprimed pagewide printheads, which do not contain any shipping fluid.
  • Memjet ® printers employing Memjet ® technology are commercially available for a number of different printing formats, including small-office-home-office (“SOHO”) printers, label printers and wideformat printers.
  • Memjet ® printers typically comprise one or more stationary inkjet printheads, which are user-replaceable.
  • SOHO printer comprises a single user-replaceable multi-colored printhead
  • high-speed inkjet press comprises a plurality of user-replaceable monochrome printheads aligned along a media feed direction
  • a wideformat printer comprises a plurality of user-replaceable printheads in a staggered overlapping arrangement so as to span across a wideformat pagewidth.
  • Replacement printheads may be shipped either ‘wet’ or ‘dry’ for installation in inkjet printers by users. Usually, printheads are shipped ‘wet’ to avoid potential problems with priming during installation. Wet-shipped printheads may be filled with either ink or a shipping fluid, which is typically an ink vehicle lacking any colorant.
  • wet-shipped printheads are less convenient for users, because ink or shipping fluid may leak from the printhead during shipment and/or spill during the installation process. Users would prefer to receive dry printheads, which are not prone to leaking or spilling fluids during shipment or installation.
  • dry-shipped printheads present challenges for ink delivery systems used to prime the dry printheads with ink. It would therefore be desirable to provide a method and system for priming a dry printhead, such as freshly installed replacement printhead in an inkjet printing system.
  • the term “ink” is taken to mean any printing fluid, which may be printed from an inkjet printhead.
  • the ink may or may not contain a colorant.
  • the term “ink” may include conventional dye-based or pigment based inks, infrared inks, fixatives ( e.g . pre-coats and finishers), 3D printing fluids and the like.
  • printer refers to any printing device for marking print media, such as conventional desktop printers, label printers, duplicators, copiers, digital inkjet presses and the like.
  • Figure 1 shows schematically an ink delivery system for a printer having a replaceable inkjet printhead
  • Figure 2 shows schematically a system for priming a dry inkjet printhead.
  • FIG. 1 there is shown schematically a printer having an ink delivery system 1 for supplying ink to a printhead 4.
  • the ink delivery system is a gravity -feed system, which is similar in function to those described in US2011/0279566 and US2011/0279562, the contents of which are herein incorporated by reference.
  • the ink delivery system comprises an intermediary ink tank 100 having an ink outlet port 106 connected to a printhead inlet port 8 of a printhead 4 via a first ink line 10.
  • An ink return port 108 of the intermediary ink tank 100 is connected to a printhead outlet port 14 of the printhead 4 via a second ink line 16.
  • the intermediary ink tank 100, the first ink line 10, the printhead 4 and the second ink line 16 define a closed fluidic loop.
  • the first ink line 10 and second ink line 16 are comprised of lengths of flexible tubing.
  • the printhead 4 is user-replaceable by means of a first coupling 3 releasably interconnecting the printhead inlet port 8 and the first ink line 10; and a second coupling 5 releasably interconnecting the printhead outlet port 14 and the second ink line 16.
  • the printhead 4 is a typically a pagewide printhead and may be, for example, a printhead as described in US2011/0279566, US 10,384,461, US 10,293,609, the contents of each of which are incorporated herein by reference.
  • Such printheads have one or more ink channels interconnecting the inlet port 8 and outlet port 14.
  • the intermediary ink tank 100 is open to atmosphere via a gas port in the form of an air vent 109 positioned in a roof of the tank. Accordingly, during normal printing, ink is supplied to the printhead 4 at a negative hydrostatic pressure (“backpressure”) under gravity.
  • backpressure negative hydrostatic pressure
  • gravity -feeding of ink from the intermediary ink tank 100, which is positioned below the printhead 4 provides a pressure-regulating system for suppling ink to the printhead at a predetermined negative hydrostatic pressure.
  • the amount of backpressure experienced at the nozzle plate 19 of the printhead 4 is determined by the height h of the nozzle plate above a level of ink 20 in the intermediary ink tank 100.
  • Ink is supplied to an ink inlet port 110 of the intermediary ink tank 100 from a bulk ink reservoir comprising a collapsible ink bag 23 housed by a cartridge 24.
  • the cartridge 24 is open to atmosphere via a cartridge vent 25 so that the collapsible ink bag 23 can collapse as ink is consumed by the system.
  • the collapsible ink bag 23 is typically an air-impermeable foil bag containing degassed ink, which is supplied to the ink inlet port 110 via an ink supply line 28.
  • the cartridge 24 is typically user-replaceable and connected to the ink supply line 28 via a suitable ink supply coupling 32.
  • a control system is used to maintain a substantially constant level of ink in the intermediary ink tank 100 and, therefore, a constant height h and corresponding backpressure.
  • a control valve 30 is positioned in the ink supply line 28 and controls a flow of ink from the cartridge 24 into the intermediary ink tank 100.
  • the control valve 30 is operated under the control of a first controller 107, which receives feedback from ‘high’ and ‘low’ sensors 102 and 104 ( e.g . optical sensors) positioned at a sidewall of the intermediary ink tank 100.
  • the first controller 107 When the level of ink 20 falls below the Tow’ sensor 104, the first controller 107 signals the valve 30 to be opened, and when the level of ink reaches the ‘high’ sensor 102, the controller signals the valve to close. In this way, the level of ink 20 in the intermediary ink tank 100 may be maintained relatively constant.
  • the intermediary ink tank 100 may be as described in, for example, US 10,427,414, the contents of which is incorporated herein by reference.
  • the closed fluidic loop incorporating the intermediary ink tank 100, the first ink line 10, the printhead 4 and the second ink line 16, facilitates priming, de-priming and other required fluidic operations.
  • the second ink line 16 includes a peristaltic pump 40 for circulating ink around the fluidic loop in clockwise direction as shown in Figure 1.
  • the pump 40 cooperates with a pinch valve arrangement 42 to coordinate various fluidic operations.
  • the pinch valve arrangement 42 comprises a first pinch valve 46 and a second pinch valve 48, and may take the form of any of the pinch valve arrangements described in, for example, US 2011/0279566; US 2011/0279562; and US9180676, the contents of which are incorporated herein by reference.
  • the first pinch valve 46 controls a flow of air through an air conduit 50, which is branched from the first ink line 10.
  • the air conduit 50 terminates at an air filter 52, which is open to atmosphere and functions as an air intake for the closed fluidic loop when required.
  • the first ink line 10 is divided into a first section 10a between the ink outlet port 106 and the air conduit 50, and a second section 10b between the printhead inlet port 8 and the air conduit 50.
  • the second pinch valve 48 controls a flow of ink through the first section 10a of the first ink line 10.
  • the pump 40, the first pinch valve 46 and the second pinch valve 48 are controlled by a second controller 44, which coordinates various fluidic operations.
  • a second controller 44 which coordinates various fluidic operations.
  • the printhead 4 draws ink from intermediary ink tank 100 at a negative backpressure under gravity.
  • the peristaltic pump 40 functions as a shut-off valve, whilst the first pinch valve 46 is closed and the second pinch valve 48 is open to allow ink flow from the ink outlet port 106 to the first port 8 of the printhead 4.
  • ink is supplied to the ink inlet port 110 of the intermediary ink tank 100, under the control of the first controller 107, to maintain a relatively constant backpressure for the printhead 4.
  • ink is circulated around the closed fluidic loop in the forward direction (i.e. clockwise as shown in Figure 1) with the control valve 30 closed.
  • the peristaltic pump 40 is actuated in the forward pumping direction whilst the first pinch valve 46 is closed and the second pinch valve 48 is open to allow ink flow from the ink outlet port 106 to the ink return port 108 via the printhead 4. Priming in this manner may be used to prime a printhead with ink.
  • the pump 40 is switched off whilst the first pinch valve 46 is closed and the second pinch valve 48 is open.
  • the “STANDBY” mode maintains a negative hydrostatic ink pressure at the printhead 4, which minimizes color mixing on the nozzle plate 19 when the printer is idle.
  • the printhead is capped in this mode to minimize evaporation of ink from the nozzles (see, for example, US2011/0279519, the contents of which are herein incorporated by reference).
  • the printer In order to replace a spent printhead 4, it is necessary to de-prime the printhead before it can be removed from the printer.
  • the first pinch valve 46 In the “DEPRIME” mode, the first pinch valve 46 is open, the second pinch valve 48 is closed and the first pump 40 is actuated in the forward direction to draw in air from atmosphere via the air conduit 50.
  • the printer is set to “NULL” mode, which isolates the printhead from the ink supply, thereby allowing safe removal of the printhead with minimal ink spillages.
  • the ink delivery system described in connection with Figure 1 is highly suitable for priming a wet printhead - that is, a printhead typically primed with a shipping fluid.
  • the pump 40 is actuated in the forward direction so as to draw ink into the printhead 4 through the inlet port 8.
  • the shipping fluid is displaced from the printhead 4 and circulates clockwise around the ink delivery system back to the intermediary tank 100 via the second ink line 16.
  • dry printheads are less suitable for priming using the ink delivery system shown in Figure 1.
  • cappers rarely provide a perfect hermetic seal around a printhead nozzle plate, especially in longer printheads. Indeed, many cappers are provided with a small breather hole to equalize pressure inside and outside the capping chamber, thereby enabling the capper to be easily uncapped from the printhead when required. Therefore, simply capping the printhead 4 is usually not an adequate solution to the problem of air being sucked into nozzles when attempting to prime the printhead.
  • FIG 2 there is shown a system suitable for priming a dry printhead 4.
  • the printhead 4 is capped by a capper 200 during priming; additionally, suction is applied to the capper 200 via a suitable vacuum source (e.g. vacuum pump) connected to the capping chamber 202.
  • a suitable vacuum source e.g. vacuum pump
  • the pump 40 when the pump 40 is actuated in the forward direction, according to the ‘PRIME’ operation described above, air cannot be sucked into the printhead 4 through the nozzles. Rather, the small vacuum pressure maintained in the capping chamber 202 of the capper 200 allows ink to be drawn into the printhead 4 via the inlet port 8, as desired, thereby priming ink channel(s) in the printhead with ink.
  • the amount of suction is controlled so as to be sufficient to overcome a pressure exerted by the pump at the nozzles of the printhead. However, the amount of suction is controlled so as to be insufficient to draw ink through the nozzles of the printhead into the capper 200.
  • ink channel(s) in the printhead 4 interconnecting the inlet port 8 and outlet port 14 may be primed with ink.
  • the second controller 44 may be used to control the amount of suction in the capping chamber 200 in concert with actuation of the pump 40. In this way, priming of dry printheads is achievable using an ink delivery system of the type that does not rely on forced one-way flow of ink through the printhead 4.

Abstract

A system for priming a dry inkjet printhead (4). The system includes: the inkjet printhead (4) having an inlet port (8) connected to an upstream ink line and an outlet port (14) connected to a downstream ink line; a pump (40) operably connected to the downstream ink line; a capper (200) engaged with printhead; a vacuum source for applying suction to a capping chamber (202) of the capper (200); and a control system for coordinating actuation of the pump and the vacuum source. In use, the pump (40) is actuated simultaneously with the vacuum source, thereby drawing ink through the printhead (4) from the inlet port to the outlet port and priming the printhead.

Description

METHOD AND SYSTEM FOR PRIMING DRY PRINTHEADS
Field of the Invention
This invention relates to method and system for priming dry printheads. It has been developed primarily for facilitating shipment of dry or unprimed pagewide printheads, which do not contain any shipping fluid.
Background of the Invention
Inkjet printers employing Memjet® technology are commercially available for a number of different printing formats, including small-office-home-office (“SOHO”) printers, label printers and wideformat printers. Memjet® printers typically comprise one or more stationary inkjet printheads, which are user-replaceable. For example, a SOHO printer comprises a single user-replaceable multi-colored printhead, a high-speed inkjet press comprises a plurality of user-replaceable monochrome printheads aligned along a media feed direction, and a wideformat printer comprises a plurality of user-replaceable printheads in a staggered overlapping arrangement so as to span across a wideformat pagewidth.
Replacement printheads may be shipped either ‘wet’ or ‘dry’ for installation in inkjet printers by users. Usually, printheads are shipped ‘wet’ to avoid potential problems with priming during installation. Wet-shipped printheads may be filled with either ink or a shipping fluid, which is typically an ink vehicle lacking any colorant.
However, wet-shipped printheads are less convenient for users, because ink or shipping fluid may leak from the printhead during shipment and/or spill during the installation process. Users would prefer to receive dry printheads, which are not prone to leaking or spilling fluids during shipment or installation.
However, dry-shipped printheads present challenges for ink delivery systems used to prime the dry printheads with ink. It would therefore be desirable to provide a method and system for priming a dry printhead, such as freshly installed replacement printhead in an inkjet printing system.
Summary of the Invention As used herein, the term “ink” is taken to mean any printing fluid, which may be printed from an inkjet printhead. The ink may or may not contain a colorant. Accordingly, the term “ink” may include conventional dye-based or pigment based inks, infrared inks, fixatives ( e.g . pre-coats and finishers), 3D printing fluids and the like.
As used herein, the term “printer” refers to any printing device for marking print media, such as conventional desktop printers, label printers, duplicators, copiers, digital inkjet presses and the like.
Brief Description of the Drawings
Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:
Figure 1 shows schematically an ink delivery system for a printer having a replaceable inkjet printhead; and
Figure 2 shows schematically a system for priming a dry inkjet printhead.
Detailed Description of the Invention
Gravity-Feed Ink Delivery System
Referring to Figure 1, there is shown schematically a printer having an ink delivery system 1 for supplying ink to a printhead 4. The ink delivery system is a gravity -feed system, which is similar in function to those described in US2011/0279566 and US2011/0279562, the contents of which are herein incorporated by reference.
The ink delivery system comprises an intermediary ink tank 100 having an ink outlet port 106 connected to a printhead inlet port 8 of a printhead 4 via a first ink line 10. An ink return port 108 of the intermediary ink tank 100 is connected to a printhead outlet port 14 of the printhead 4 via a second ink line 16. Hence, the intermediary ink tank 100, the first ink line 10, the printhead 4 and the second ink line 16 define a closed fluidic loop. Typically, the first ink line 10 and second ink line 16 are comprised of lengths of flexible tubing.
The printhead 4 is user-replaceable by means of a first coupling 3 releasably interconnecting the printhead inlet port 8 and the first ink line 10; and a second coupling 5 releasably interconnecting the printhead outlet port 14 and the second ink line 16. The printhead 4 is a typically a pagewide printhead and may be, for example, a printhead as described in US2011/0279566, US 10,384,461, US 10,293,609, the contents of each of which are incorporated herein by reference. Such printheads have one or more ink channels interconnecting the inlet port 8 and outlet port 14.
The intermediary ink tank 100 is open to atmosphere via a gas port in the form of an air vent 109 positioned in a roof of the tank. Accordingly, during normal printing, ink is supplied to the printhead 4 at a negative hydrostatic pressure (“backpressure”) under gravity. In other words, gravity -feeding of ink from the intermediary ink tank 100, which is positioned below the printhead 4, provides a pressure-regulating system for suppling ink to the printhead at a predetermined negative hydrostatic pressure. The amount of backpressure experienced at the nozzle plate 19 of the printhead 4 is determined by the height h of the nozzle plate above a level of ink 20 in the intermediary ink tank 100.
Ink is supplied to an ink inlet port 110 of the intermediary ink tank 100 from a bulk ink reservoir comprising a collapsible ink bag 23 housed by a cartridge 24. The cartridge 24 is open to atmosphere via a cartridge vent 25 so that the collapsible ink bag 23 can collapse as ink is consumed by the system. The collapsible ink bag 23 is typically an air-impermeable foil bag containing degassed ink, which is supplied to the ink inlet port 110 via an ink supply line 28. The cartridge 24 is typically user-replaceable and connected to the ink supply line 28 via a suitable ink supply coupling 32.
A control system is used to maintain a substantially constant level of ink in the intermediary ink tank 100 and, therefore, a constant height h and corresponding backpressure. As shown in Figure 1, a control valve 30 is positioned in the ink supply line 28 and controls a flow of ink from the cartridge 24 into the intermediary ink tank 100. The control valve 30 is operated under the control of a first controller 107, which receives feedback from ‘high’ and ‘low’ sensors 102 and 104 ( e.g . optical sensors) positioned at a sidewall of the intermediary ink tank 100. When the level of ink 20 falls below the Tow’ sensor 104, the first controller 107 signals the valve 30 to be opened, and when the level of ink reaches the ‘high’ sensor 102, the controller signals the valve to close. In this way, the level of ink 20 in the intermediary ink tank 100 may be maintained relatively constant. The intermediary ink tank 100 may be as described in, for example, US 10,427,414, the contents of which is incorporated herein by reference.
The closed fluidic loop, incorporating the intermediary ink tank 100, the first ink line 10, the printhead 4 and the second ink line 16, facilitates priming, de-priming and other required fluidic operations. The second ink line 16 includes a peristaltic pump 40 for circulating ink around the fluidic loop in clockwise direction as shown in Figure 1. The pump 40 cooperates with a pinch valve arrangement 42 to coordinate various fluidic operations. The pinch valve arrangement 42 comprises a first pinch valve 46 and a second pinch valve 48, and may take the form of any of the pinch valve arrangements described in, for example, US 2011/0279566; US 2011/0279562; and US9180676, the contents of which are incorporated herein by reference.
The first pinch valve 46 controls a flow of air through an air conduit 50, which is branched from the first ink line 10. The air conduit 50 terminates at an air filter 52, which is open to atmosphere and functions as an air intake for the closed fluidic loop when required.
By virtue of the air conduit 50, the first ink line 10 is divided into a first section 10a between the ink outlet port 106 and the air conduit 50, and a second section 10b between the printhead inlet port 8 and the air conduit 50. The second pinch valve 48 controls a flow of ink through the first section 10a of the first ink line 10.
The pump 40, the first pinch valve 46 and the second pinch valve 48 are controlled by a second controller 44, which coordinates various fluidic operations. From the foregoing, it will be appreciated that the ink delivery system shown in Figure 1 provides a versatile range of fluidic operations. Table 1 describes various pinch valve and pump states for some example fluidic operations used in the printer 1. Of course, various combinations of these example fluidic operations may be employed. Table 1. Example Fluidic Operations for Printer 1
During normal printing (“PRINT” mode), the printhead 4 draws ink from intermediary ink tank 100 at a negative backpressure under gravity. In this mode, the peristaltic pump 40 functions as a shut-off valve, whilst the first pinch valve 46 is closed and the second pinch valve 48 is open to allow ink flow from the ink outlet port 106 to the first port 8 of the printhead 4. During printing, ink is supplied to the ink inlet port 110 of the intermediary ink tank 100, under the control of the first controller 107, to maintain a relatively constant backpressure for the printhead 4.
During printhead priming or flushing (“PRIME” mode), ink is circulated around the closed fluidic loop in the forward direction (i.e. clockwise as shown in Figure 1) with the control valve 30 closed. In this mode, the peristaltic pump 40 is actuated in the forward pumping direction whilst the first pinch valve 46 is closed and the second pinch valve 48 is open to allow ink flow from the ink outlet port 106 to the ink return port 108 via the printhead 4. Priming in this manner may be used to prime a printhead with ink.
In the “STANDBY” mode, the pump 40 is switched off whilst the first pinch valve 46 is closed and the second pinch valve 48 is open. The “STANDBY” mode maintains a negative hydrostatic ink pressure at the printhead 4, which minimizes color mixing on the nozzle plate 19 when the printer is idle. Usually, the printhead is capped in this mode to minimize evaporation of ink from the nozzles (see, for example, US2011/0279519, the contents of which are herein incorporated by reference).
In order to replace a spent printhead 4, it is necessary to de-prime the printhead before it can be removed from the printer. In the “DEPRIME” mode, the first pinch valve 46 is open, the second pinch valve 48 is closed and the first pump 40 is actuated in the forward direction to draw in air from atmosphere via the air conduit 50. Once the printhead 4 has been deprimed of ink, the printer is set to “NULL” mode, which isolates the printhead from the ink supply, thereby allowing safe removal of the printhead with minimal ink spillages.
From the foregoing, it will be appreciated that a number of fluidic operations may be performed using the ink delivery system described above in connection with Figure 1.
Priming Dry Printhead 4
The ink delivery system described in connection with Figure 1 is highly suitable for priming a wet printhead - that is, a printhead typically primed with a shipping fluid. In the ‘PRIME’ mode, the pump 40 is actuated in the forward direction so as to draw ink into the printhead 4 through the inlet port 8. In this way, the shipping fluid is displaced from the printhead 4 and circulates clockwise around the ink delivery system back to the intermediary tank 100 via the second ink line 16. (Any dilution of ink by the shipping fluid is virtually unnoticeable to the user, or quickly mitigated by spitting ink from the printhead 4). However, dry printheads are less suitable for priming using the ink delivery system shown in Figure 1. This is because actuation of the pump 40 in the forward direction tends to suck air into the printhead 4 via ink ejection nozzles instead of drawing fresh ink into the printhead through the inlet port 8. The problem is particularly exacerbated in longer printheads e.g. printheads longer than 200 mm or printheads longer than 250 mm. One means for overcoming this problem of priming dry printheads is to seal the nozzles so as to prevent air being sucked into the printhead 4. Printhead cappers are well known to those skilled in the art and are designed to inhibit dehydration of ink from nozzles during idle periods (see, for example, the capper described in US 10,518,536, the contents of which is incorporated herein by reference). However, cappers rarely provide a perfect hermetic seal around a printhead nozzle plate, especially in longer printheads. Indeed, many cappers are provided with a small breather hole to equalize pressure inside and outside the capping chamber, thereby enabling the capper to be easily uncapped from the printhead when required. Therefore, simply capping the printhead 4 is usually not an adequate solution to the problem of air being sucked into nozzles when attempting to prime the printhead.
In Figure 2, there is shown a system suitable for priming a dry printhead 4. In this system, the printhead 4 is capped by a capper 200 during priming; additionally, suction is applied to the capper 200 via a suitable vacuum source (e.g. vacuum pump) connected to the capping chamber 202.
Therefore, when the pump 40 is actuated in the forward direction, according to the ‘PRIME’ operation described above, air cannot be sucked into the printhead 4 through the nozzles. Rather, the small vacuum pressure maintained in the capping chamber 202 of the capper 200 allows ink to be drawn into the printhead 4 via the inlet port 8, as desired, thereby priming ink channel(s) in the printhead with ink. The amount of suction is controlled so as to be sufficient to overcome a pressure exerted by the pump at the nozzles of the printhead. However, the amount of suction is controlled so as to be insufficient to draw ink through the nozzles of the printhead into the capper 200. Thus, ink channel(s) in the printhead 4 interconnecting the inlet port 8 and outlet port 14 may be primed with ink.
The second controller 44 may be used to control the amount of suction in the capping chamber 200 in concert with actuation of the pump 40. In this way, priming of dry printheads is achievable using an ink delivery system of the type that does not rely on forced one-way flow of ink through the printhead 4.
It will, of course, be appreciated that the present invention has been described by way of example only and that modifications of detail may be made within the scope of the invention, which is defined in the accompanying claims.

Claims

1. A system for priming a dry inkjet printhead, said system comprising: the inkjet printhead having an inlet port connected to an upstream ink line and an outlet port connected to a downstream ink line; a pump operably connected to the downstream ink line; a capper engaged with the printhead; a vacuum source for applying suction to a capping chamber of the capper; and a control system for coordinating actuation of the pump and the vacuum source, wherein, in use, the pump is actuated simultaneously with the vacuum source, thereby drawing ink through the printhead from the inlet port to the outlet port and priming the printhead.
2. The system of claim 1 further comprising an ink tank, wherein the upstream and downstream ink lines are connected to the ink tank to form a closed fluidic loop with the printhead.
3. The system of claim 2, wherein the ink tank is replenishable from a bulk ink supply.
4. The system of claim 3, wherein the ink tank is positioned below a height of the printhead for gravity control of ink pressure in the printhead.
5. The system of claim 1, wherein the pump is a one-way pump.
6. The system of claim 5, wherein the pump is an inline peristaltic pump.
7. The system of claim 1, wherein the suction is sufficient to overcome a pressure exerted by the pump at the nozzles of the printhead.
8. The system of claim 1, wherein the suction is insufficient to draw ink through nozzles of the printhead.
9. A method of priming a dry inkjet printhead having an inlet port and an outlet port, said method comprising the steps of: applying suction to nozzles of the printhead; and pumping ink through the printhead from the inlet port to the outlet port, wherein the suction is insufficient to draw ink through the nozzles.
10. The method of claim 9, wherein the suction is sufficient to overcome a pressure exerted by the pump at the nozzles.
EP21701123.8A 2020-02-13 2021-01-19 Method and system for priming dry printheads Active EP4069517B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202062976213P 2020-02-13 2020-02-13
PCT/EP2021/051089 WO2021160385A1 (en) 2020-02-13 2021-01-19 Method and system for priming dry printheads

Publications (2)

Publication Number Publication Date
EP4069517A1 true EP4069517A1 (en) 2022-10-12
EP4069517B1 EP4069517B1 (en) 2023-06-07

Family

ID=74194752

Family Applications (1)

Application Number Title Priority Date Filing Date
EP21701123.8A Active EP4069517B1 (en) 2020-02-13 2021-01-19 Method and system for priming dry printheads

Country Status (6)

Country Link
US (1) US20210252867A1 (en)
EP (1) EP4069517B1 (en)
JP (1) JP2023514799A (en)
CN (1) CN115087548A (en)
AU (1) AU2021221024A1 (en)
WO (1) WO2021160385A1 (en)

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002234194A (en) * 2001-02-09 2002-08-20 Canon Inc Ink jet recorder and method for restoring the same
JP4511141B2 (en) * 2002-11-26 2010-07-28 セイコーエプソン株式会社 Functional liquid filling device for droplet discharge head, droplet discharge device, electro-optical device, and electro-optical device manufacturing method
US7841706B2 (en) * 2004-06-01 2010-11-30 Canon Finetech, Inc. Ink supply apparatus and method for controlling the ink pressure in a print head
GB2447919B (en) * 2007-03-27 2012-04-04 Linx Printing Tech Ink jet printing
US20110026046A1 (en) * 2009-07-31 2011-02-03 Silverbrook Research Pty Ltd Wide format printer with scanner to align printhead assembly
TWI513597B (en) 2010-05-17 2015-12-21 Memjet Technology Ltd System for coupling fluid supply to printhead
US8764141B2 (en) 2010-05-17 2014-07-01 Zamtec Ltd System for shaping media at printhead
TW201208895A (en) 2010-05-17 2012-03-01 Silverbrook Res Pty Ltd System for transporting media in printer
JP6221225B2 (en) * 2012-12-18 2017-11-01 セイコーエプソン株式会社 Liquid supply device and liquid ejection device
JP6265391B2 (en) 2013-01-15 2018-01-24 メムジェット テクノロジー リミテッド Small pinch valve
TWI715755B (en) 2016-05-02 2021-01-11 愛爾蘭商滿捷特科技公司 Monochrome inkjet printhead configured for high-speed printing
TW201838829A (en) 2017-02-06 2018-11-01 愛爾蘭商滿捷特科技公司 Inkjet printhead for full color pagewide printing
US10518536B2 (en) 2017-02-15 2019-12-31 Memjet Technology Limited Capping assembly for inkjet printhead
AU2018223066B2 (en) 2017-02-24 2020-05-21 Memjet Technology Limited Ink tank for regulating ink pressure
JP7005908B2 (en) * 2017-02-27 2022-01-24 セイコーエプソン株式会社 Liquid injection head unit and liquid injection device
JP6551450B2 (en) * 2017-03-31 2019-07-31 ブラザー工業株式会社 Printing device
JP6571725B2 (en) * 2017-07-24 2019-09-04 ローランドディー.ジー.株式会社 Diaphragm pump, ink supply system, and ink jet printer
JP7040009B2 (en) * 2017-12-27 2022-03-23 ブラザー工業株式会社 Inkjet printers, inkjet printer control methods, and programs
JP7064168B2 (en) * 2018-01-26 2022-05-10 株式会社リコー Device that discharges liquid
JP6969418B2 (en) * 2018-02-07 2021-11-24 セイコーエプソン株式会社 How to replace the liquid injection device and liquid injection head

Also Published As

Publication number Publication date
WO2021160385A1 (en) 2021-08-19
EP4069517B1 (en) 2023-06-07
CN115087548A (en) 2022-09-20
US20210252867A1 (en) 2021-08-19
AU2021221024A1 (en) 2022-07-21
JP2023514799A (en) 2023-04-11

Similar Documents

Publication Publication Date Title
US9272523B2 (en) Printer configured for optimized printing
EP2844488B1 (en) Printer configured for efficient air bubble removal
AU2018223066B2 (en) Ink tank for regulating ink pressure
US20190299641A1 (en) Method of de-aerating filter chamber
US11198303B2 (en) Ink delivery system incorporating regulator tank
EP4069517B1 (en) Method and system for priming dry printheads
WO2015150148A1 (en) Printer configured for optimized priming
US11607886B2 (en) Ink tank with integrated filter

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20220707

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20230303

RIN1 Information on inventor provided before grant (corrected)

Inventor name: YOURLO, ZHENYA

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230424

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: AT

Ref legal event code: REF

Ref document number: 1573876

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230615

Ref country code: DE

Ref legal event code: R096

Ref document number: 602021002815

Country of ref document: DE

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230907

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1573876

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230908

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231007

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231009

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231007

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230607

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602021002815

Country of ref document: DE

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT